In a documentary from the Discovery Channel on the search for extraterrestrial life, Stephen Hawking provides an extraordinarily candid example of the fallacious materialist logic for why extraterrestrial life "must" be possible.

Around 1:15 of the clip below, Hawking states:

The life we have on earth must have spontaneously generated itself. It must therefore be possible for life to be generated spontaneously elsewhere in the universe.

The gaping hole in Hawking's logic should be immediately apparent to anyone willing to think critically and skeptically: If we haven't yet explained how life could have spontaneously generated on earth, how do we know that it can be generated spontaneously elsewhere in the universe?

What makes Hawking's position even worse is that in this clip he admits that "we don't understand how life formed."

So according to Hawking, "we don't understand how life formed," but he knows that "the life we have on earth must have spontaneously generated itself." Hawking might be, as the documentary puts it, "one of the greatest minds of our generation," but as anti-ID biochemist Russell Doolittle once said to me in grad school (when attacking Michael Behe), smart guys are great rationalizers.

To charitably apply Hawking's logic in a less biased fashion, perhaps we might say something like this: Whatever you believe about origins, obviously life arose on earth somehow. So whatever mechanism generated life on earth, perhaps it could have been at work elsewhere. For example, there's no reason scientifically to presume that intelligent design precludes the possibility of extraterrestrial life. But make no mistake: if ET life is ever found, the media will trumpet it as the grand validation of materialism. Perhaps it is--but only if you use Stephen Hawking's fallacious logic.

What else would you expect from the guy that said "Because there is a law such as gravity, the universe can and will create itself from nothing"? (Stephen Hawking and Leonard Mlodinow, The Grand Design, p. 180 (Bantam, 2010).)